1. Field
Exemplary embodiments of the present invention relate to a transistor and, more particularly, to a transistor having a tungsten-based buried gate structure and a method for fabricating the same.
2. Description of the Related Art
A metal gate electrode may be used for the gate electrode of a transistor. The gate resistance may be reduced by the metal gate electrode. Additionally, the channel dose may be reduced since the metal gate electrode has a high work function. Therefore, the performance of the transistor may be improved by reducing the amount of leakage current.
The metal gate electrode includes a barrier layer for protecting the gate dielectric layer from being attacked. A metal nitride, such as a titanium nitride (TiN), is generally used for the barrier layer.
However, since the metal nitride has high resistivity, there is a limitation in reducing the gate resistance of the metal gate electrode.